Non-Rival Property of Public Goods

Steps:

• Recall that public goods are non-rivalrous if one person's use does not reduce availability for others.
• Examine choices for statements matching this definition.
• Eliminate options describing excludability or other issues.
• Confirm the match with the core economic trait.

Why B is correct:

• Non-rival nature is defined in economics as consumption by one individual not diminishing the supply for others, as in national defense where one citizen's protection doesn't reduce it for anyone else.

Why the others are wrong:

• A describes non-excludability, the inability to prevent free riders.
• C refers to externalities or underconsumption due to market failure, not rivalry.
• D implies infinite supply but ignores that rivalry concerns consumption impact, not total quantity.

Final answer: B